In recent years, as improvements in the integration and miniaturization of the semiconductor device progresses, there has been a steady shift from the present sub-half-micron range to the sub-quarter-micron range. In this quest to develop the next generation of semiconductor devices, film deposition techniques are exceedingly important.
In response to demands for improvements in integration and further miniaturization, switching from aluminum-based materials to copper-based materials being used as interconnective material is under consideration. Presently, metalorganic chemical vapor deposition (MOCVD), which is performed by vaporizing an organic metal, such as (hfac)Cu+1(tmvs), which is usually fluid at room temperature and under normal pressure, introducing it to the process chamber, and depositing a film by causing a pyrolytic decomposition reaction to occur on the wafer being held in said process chamber, is put to use.
Such conventional MOCVD processes thus provide superb step coverage and are extremely effective in the fabrication of very thin films. However, with these MOCVD processes, at times when it is necessary to guarantee a sufficient layer thickness, for example during the step of filling in contact holes, problems such as the lack of efficiency develop. It takes time to fill in the hole completely since there is a limit to the thickness of the layer which can be accumulated during a certain length of time due to the low amounts of the organic metal itself existing in the process chamber, resulting from the low pressure in the process chamber. There is an additional danger of the vaporized organic metal reacting inside the supply pipeline and clogging the pipes.
The present invention takes the above information into consideration and aims to provide a film deposition process and apparatus, which use organometallic fluids, wherewith highly effective film deposition can be performed without causing blockage in the supply pipeline.